From: Gary Watson <pfharlock@...>
Date: 2005-12-06T00:57:33+09:00
Subject: Re: increasing counter whithin loop?

a = ["a", "b", "c", "d", "e"]

temp = nil

p a.select {|x| if temp == "b" then temp = nil; next end; temp = x;true}


outputs

["a", "b", "d", "e"]

Probably could be cleaner.

Patrick Gundlach wrote:
> Hi,
> 
> a very basic question...
> 
> I'd like to output the sequence "a b d e", by testing if the current
> element is == "b" then skip the next element and continue the loop. The
> obvious solution doesn't look rubyish to me, how could I use the first
> or second attempt to get the desired solution?
> 
> Patrick
> --------------------------------------------------
> a=%w( a b c d e )
> 
> # incorrect, outputs "a b c d e"
> 0.upto(a.size - 1) do |i|
>   puts a[i]
>   if a[i]=="b"
>     # skip next element
>     # but i won't get affected
>     i += 1
>   end
> end
> 
> # incorrect, outputs "a b c d e"
> for i in 0...a.size
>   puts a[i]
>   if a[i]=="b"
>     # skip next element
>     # but i won't get affected
>     i += 1
>   end
> end
> 
> # incorrect, outputs nothing... is there a next_next ?
> a.each do |elt|
>   puts elt
>   if elt=="b"
>     # skip next element
>     # ??
>   end
> end
> 
> # this one works, but is ugly
> i=0
> while i < a.size
>   puts a[i]
>   if a[i]=="b"
>     # skip next element
>     i += 1
>   end
>   i += 1
> end